Device and Process for Controlling Compaction Based on Previously Mapped Data

ABSTRACT

This disclosure provides a system and method for compacting materials, and more specifically, a system and method for proactively varying compaction effort over a mat of materials located at a worksite area responsive to previously mapped data relating to the compaction makeup of that specific worksite area.

TECHNICAL FIELD

The disclosure relates generally to machines and control strategies used in compacting materials, and relates more particularly to proactively varying compaction effort over a mat of material located at a worksite area responsive to previously mapped data relating to the compaction makeup of that specific worksite area.

BACKGROUND

In the construction industry, the quality and durability of the final surface being laid (whether asphalt, or concrete, or other) is highly dependent on the substrate or mat materials located thereunder. Accordingly, in site preparation compaction of the substrate materials must be carefully considered and monitored in order to provide the desired final surface. Given various site condition variability, substrate compaction/makeup can vary significantly over varying locations at the site. Additionally, there are instances when multiple compaction efforts may be made by multiple machines over the same site prior to the laying of the final surface thereover.

In general desired site preparation by compaction is achieved by driving, pushing or towing a machine having rotating drums across the substrate of interest to increase its density and uniformity. Compactors are often equipped with vibratory apparatuses to increase and control energy transfer between the compactor and the substrate. As noted above, different substrates, and similar substrates having different qualities such as moisture level, thickness and other qualities, will tend to respond differently to compactor interaction with the substrate. The response of a material to compactor interaction can affect the smoothness that is ultimately achievable in the final surface.

Various machines are known in the art, for preparing a subgrade prior to preparing the mat upon which the final surface will be laid. These machines include, but are not limited to, cold planers, recyclers and other reclaiming machines. In general, these machines travel across a region of a work area upon which a mat of material is to be paved, and process the existing material, either by grinding up, mixing and re-depositing the material, or by cutting away a layer of material for disposal elsewhere.

As noted above, different materials may have widely varying “compaction responses” or changes in properties resulting from coverage with a compactor machine. For instance, sandy or granular soils tend to exhibit a different change in relative stiffness than do soils high in clay content each time a compactor is passed over a given region. Local variations in material composition or moisture content within a work area, as well as changes in moisture content over time can also result in non-uniformity in stiffness even where compactor coverage has been uniform. Like many heavy-duty construction machines, compactors can be quite expensive to operate, and thus unnecessary work or remedial actions create undesired expense. It is additionally noted that excess compaction may be problematic not just due to unnecessary wasted time and expense, but also due to the fact that excess compaction can lead to de-compaction or crushing of aggregate material due to high amplitude from a vibratory compaction system or over-compaction from excessive compaction effort.

In this regard, substantial effort has been made to test substrate quality, compaction, etc. prior to and during final compaction before the final surface is laid thereover. For example, some known methods include detecting the quality of the compaction by taking a boring sample and analyzing the sample in a laboratory. At least some of the drawbacks of this procedure include that it is time consuming, the measurement is performed only by way of spot checks and only after termination of at least the first compacting process thus making it difficult, if not impossible to adjust compaction effort during compaction. Other known methods of compaction testing include the use of electronic probes which are manually applied to the site and are capable of detecting a degree of compaction existing at a given spot. Such electronic probes offer the advantage of delivering individual results already while the compacting is still in progress. Also in this measuring method, however, the spot-wise character of the measurements makes it impossible to obtain results on the whole treated surface.

Further intelligent compaction technology is growing in acceptance and use. For example, U.S. Pat. No. 8,057,124 B2, assigned to Wacker Neuson Produktion GmbH & Co., discloses a method and device for measuring soil parameters. That patent discloses a system and method for approximating the actual gradient of the contact force and a contact surface parameter that takes into account the geometry and shape of the contact surface to calculate a dynamic modulus of deformation. Additionally, U.S. Pat. No. 7,873,492 assigned to Hamm AG discloses a method for predicting compaction over an entire subsurface utilizing data taken from subsegments thereof. While the systems and methods disclosed in these patents may have some utility, none provide a proactive control of a compaction device before the compaction device reaches the previously mapped worksite area.

SUMMARY

In one aspect, a system for proactively varying compaction effort over a mat of material located at a worksite area responsive to previously mapped data relating to the compaction makeup thereof is provided. More specifically, in some aspects of the disclosure, systems and methods for proactively varying compaction effort over a mat of materials comprising a worksite using historical compaction data (or compaction data from other sources) with precise location and machine measurement data as to that worksite area is disclosed. In aspects of the disclosure, the additional amount of compaction needed to provide the exact desired amount of compaction may be calculated. In accordance therewith, a compaction machine having variable compaction effort, such as variable vibratory frequency and/or amplitude, may be automatically and proactively adjusted based upon the aforementioned historical data or other compaction data in a proactive manner to precisely provide the amount of compaction necessary to provide the total final desired compaction.

In accordance with aspects of the disclosure, proactive changes in vibratory frequency, amplitude, etc., may be made in real-time as the compaction machine approaches and works on a previously mapped worksite area requiring a change in compaction effort to provide the desired total compaction. The disclosure thus avoids reactive changes to compaction effort occurring after the compaction machine has arrived at or even passed the specific worksite area or failing to provide the total amount of compaction necessary in a single pass. Additionally, the disclosed system may advantageously prevent operation of the compaction machine at the wrong worksite location, or in circumstances where more than one machine is being used on a worksite, prevent use of the wrong machine in the wrong location. Further in accordance with the disclosure, the disclosed system may be used to control multiple compactors to provide desired compaction for subsegments of the worksite.

In one aspect of the disclosure, the worksite information may be supplied from multiple sources, including, but not limited to, a prior pass by the compaction machine, other worksite machines, or specifically designed and implemented worksite surveys, testing, etc. Additional embodiments of the present disclosure include a system for controlling construction machine traffic on a worksite area including all machines causing ground compaction, not just purpose-built compaction machines Additionally, the present disclosure may provide automated control of all compaction machines on a worksite to insure the right machine is used at the right location to proactively provide desired compaction.

BRIEF DESCRIPTION OF THE DRAWING(S)

FIG. 1 is a side diagrammatic view of an exemplary compactor for use in accordance with aspects of the disclosure; and

FIG. 2 is a pictorial view of a display illustrating a mapped paving worksite according to aspects of the disclosure.

DETAILED DESCRIPTION

The disclosure relates generally to a system and method for proactively varying compaction effort over a mat of materials located at a worksite area responsive to previously mapped data relating to the compaction makeup of that specific worksite area. Specifically, the disclosure relates to proactive changes in vibratory frequency, amplitude, etc., that may be made in real-time to compaction machines as the compaction machines approach and work on worksite locations that have previously been mapped with specific compaction information related to subsegments of the worksite.

In accordance with the foregoing, FIG. 1 illustrates a side view of a compactor 10 working on a mat of materials Z located generally at a worksite area. In particular, FIG. 1 illustrates an exemplary compactor 10 of the self-propelled type that can travel over a surface S under its own power that may implement aspects of the disclosure. In particular, FIG. 1 depicts a smooth double drum compactor 10 of the type commonly used on asphalt and also on fine grained base materials such as fill sand. It is to be understood, however, that the present disclosure also applies to work machines, including compactors, with various styles of tips or “teeth” that are commonly used on earth material bases and sub bases for earthworks construction, particularly on cohesive fill materials. Additionally, work machines such as self-propelled two-wheel and four-wheel compactors, tow-behind systems, single drum “padfoot” vibratory machines, four wheel “tamping” foot machines, the traditional “sheep's foot” towed rollers, etc. are also known and maybe used in accordance with the disclosure. Additionally, aspects of the present disclosure may involve other types of worksite machines that may compact a worksite area (whether designed to or not), including, but not limited to: hauling units, such as scrapers; articulated trucks and on-road trucks, such as side dumps, or rear dumps; paving machines; cold planers; reclaimers; etc.

In accordance with aspects of the disclosure, the compactor 10 may include a body or frame 12 that inter-operatively connects and associates the various physical and structural features that enable the compactor 10 to function. These features may include an operator cab 20 that is mounted on top of the frame 12 from which an operator may control and direct operation of the compactor 10. Additionally, a steering system 21 and similar controls may be located within the operator cab 20. To propel the compactor 10 over the surface S, a power system (not shown), such as an internal combustion engine, can also be mounted to the frame 12 and can generate power that is converted to physically move the compactor 10. As shown in FIG. 2, one or more other implements may be connected to the compactor 10, including, but not limited to a blade 36. Such devices may include, but are not limited to devices for loading, lifting, and brushing, and may include, for example, buckets, forked lifting devices, brushes, grapples, cutters, shears, breakers/hammers, augers, and others.

To enable physical motion of the compactor 10, the compactor 10 includes a first roller drum 24 and a second roller drum 22 that are in rolling contact with the surface S. For reference purposes, the compactor 10 can have a typical direction of travel such that the first roller drum 24 may be considered the forward roller drum and the second roller drum 22 considered the rearward roller drum. The first (forward) and second (rearward) roller drums 24, 22 can be cylindrical structures that are rotatably coupled to and can rotate with respect to the frame 12. Because of their forward and rearward positions and their dimensions, the first (forward) and second (rearward) roller drums 24, 22 support the frame 12 of the compactor 10 above the surface S and allow it to travel over the surface S. Each drum 24, 22 may be provided with a vibratory apparatus, each of which may have an adjustable vibration amplitude, adjustable vibration frequency and/or adjustable vibration direction. Varying energy transfer could also include turning one or both of vibratory apparatuses on or off.

To facilitate control and coordination of the compactor 10, a controller 39 such as an electronic control unit 40 may be utilized. The main interface (not shown) of the controller 39 may be located in the operator cab 20 for access by the operator and may communicate with the steering system 21, the power system, and with various other sensors and controls on the compactor 10. While the controller 39 illustrated in FIG. 1 is represented as a single unit, in other embodiments of the disclosure, the controller 39 may be distributed as a plurality of distinct but interoperating units, incorporated into another component, or located at a different location on or off the compactor 10.

The controller 39 may include sensors 32 configured to sense a parameter indicative of the acceleration, velocity, and/or force of a component of the compactor 10. The components may include the first (forward) and/or second (rearward) roller drums 24, 22, the compactor frame 12, or the like. Additionally, there may be more than one type of sensor located on the compactor 10. For example, there may be sensors sensing the vertical acceleration of the roller drums 22, 24. Such sensors may be accelerometers and may include, but are not limited to, laser accelerometers, low frequency accelerometers, bulk micromachined capacitive accelerometers, strain gauge accelerometers, and bulk micromachined piezoelectric accelerometers among others.

In one aspect of the disclosure, the sensors 32 may sense force. In accordance with such an embodiment, the sensors 32 may be, but are not limited to, load cells, strain gauges, or the like. In another aspect, the sensors 32 may be located at or close to a center point of axle 30, at or close to a longitudinal centerline of frame 12. The transmitted signals may include sonic signals, RF signals, or laser signals, for example, transmitted via a transmitter 34 mounted with sensors 32 in a housing 38. Sensors 32 may include a non-contact sensor such as the examples noted above.

Controller 39 may further include a phase sensor 33. Phase sensor 33 may be used to measure the phase angle of a vibratory force imparted by the first (forward) and/or second (rearward) roller drums 24, 22 to the ground. The phase angle may be measured in real time and transmitted to an electronic controller (not shown) for later use in accordance with aspects of the disclosure. Controller 39 may further include a location sensor 46 resident on compactor 10 which receives global or local positioning data used in establishing and tracking geographic position of compactor 10 within a worksite area. In one aspect, further described herein, data received via the location sensor 46 may be linked with data received from sensors 32, 33 to map compaction data relative to the position data of the compactor 10 for use in accordance with the disclosure. Controller 39 may be used to calculate the exact amount of additional compaction needed to provide the total desired amount of compaction to a particular worksite area. Controller 39 may also be used to control aspects of the vibratory apparatuses provided on each drum 24, 22 in order to control the vibration amplitude, vibration frequency and/or vibration direction to provide the desired compaction as is known to those of ordinary skill in the art. Controller 39 may continuously control the vibratory apparatuses in real-time, varying the vibration amplitude, vibration frequency, and/or vibration direction to provide the total desired amount of compaction as calculated by the controller 39.

Controller 39 may further include an electronic control unit 40 which includes at least one data processor 42 and a computer readable memory 44. Electronic control unit 40 may be coupled with sensors 32, 33 and also with location sensor 46, and may be configured to output a signal responsive to inputs received with respect to previously mapped worksite compaction data. As shown in FIG. 1, a display 48 also may be coupled with electronic control unit 40 and may be positioned in the operator cab 20 to display various data to an operator relating to machine position, previously mapped compaction data, or still other parameters. In the illustrated aspect, the controller 39 is resident on the compactor 10.

It should be appreciated that in other aspects, controller 39 or parts thereof might be located remotely from the compactor 10, such as at an on-site or offsite management office. In such an aspect, data gathered relating to position of compactor 10 and compaction data might be transmitted to a remote computer, processed, and control commands sent to the compactor 10 to direct an operator to take or forego certain actions, or to direct compactor 10 to autonomously take or forego certain actions. Taking actions in response to the previously mapped compaction data when combined with current position data might include commencing travel of compactor 10 within a work area, stopping travel of compactor 10 within a work area, or redirecting or otherwise changing a planned compactor 10 travel path or coverage pattern. Computer readable memory 44 may store computer executable code including a control algorithm for determining exact variation of vibratory amplitude, frequency, and/or speed of the compactor over a worksite area in order to achieve final desired compaction of the substrate Z.

In accordance with the disclosure, FIG. 2 is a pictorial view of a display illustrating a mapped compaction state of a worksite. The worksite has been fragmented into smaller work areas, or subsegments, of length L and width W. The subsegments represent specific information collected relating to each subsegment relevant to the degree of compaction thereof. In accordance with aspects of the disclosure, the controller 39, may then calculate the additional amount of compaction needed, if any, to provide the total desired amount of compaction for each subsegment. Thus having been provided with a map of the degree of compaction of the subsegments of the worksite, and utilizing the location sensor 46, compaction effort of the compactor 10 may be adjusted in real-time by continuously varying compactor 10 speed, and/or vibratory amplitude or frequency of the drums 24, 22 proactively to provide the exact total desired compaction for each subsegment needing additional compaction. In one embodiment, the control may be made by an operator manually. In other embodiments, the compaction effort may be adjusted automatically by the controller 39 through an algorithm in the electronic control unit 40.

In accordance with aspects of the disclosure, the information as to compaction status of the subsegments may be derived from multiple available sources including, but not limited to, worksite machines (including other compactors), or specifically designed and implemented worksite surveys, testing, probing, etc. Further, the movement of worksite machines other than compactors may be controlled over the various subsegments to provide compaction (where additional marginal compaction is desired) or to prevent compaction, by diverting worksite machines away from subsegments that are properly compacted. Such control may be in the form of messages transmitted to the operators of the worksite machines or by automatic control thereof.

More specifically, in aspects of the disclosure, the map of subsegments of the work area may designate certain areas as compacted as desired and thus “off limits” to further worksite machine traffic over such subsegments. In accordance therewith, either a message indicating that a worksite machine is approaching a fully compacted subsegment is sent to the operator of the machine in real-time warning of the approaching fully compacted subsegment or the worksite machine is automatically controlled to avoid the subsegment.

INDUSTRIAL APPLICABILITY

The present disclosure is useful in a multitude of construction applications. By utilizing aspects of the present disclosure to proactively vary compaction effort over a mat of material located at a worksite area responsive to previously mapped data, unnecessary and undesired compaction effort may be prevented. Utilizing automatic control thereof may prevent operator error and allow more efficient worksite control.

In accordance with aspects of the disclosure, based upon previously developed compaction data as to worksite subsegments, a map may be created of the existing compaction status of the subsegments. Utilizing the existing map, all worksite traffic, including, but not limited to, compaction machine traffic, may be monitored and controlled. Further in accordance with aspects of the disclosure, compaction equipment may continue to take compaction readings to confirm that desired compaction has been achieved on a subsegment by subsegment basis and mapping may be updated in accordance therewith. In specific embodiments of the disclosure, compaction effort is controlled through varying compactor roller vibratory frequency and/or amplitude, and/or compactor speed over worksite subsegments.

In accordance with other embodiments of the disclosure, compactor 10 travel speed, compactor travel direction, and/or compactor effort may be controlled via electronic control unit 40 may be through access to a computer network via transmitter (not shown). The communication channels that may be used in connection therewith may be any type of wired or wireless electronic communications network, such as, e.g., a wired/wireless local area network (LAN), a wired/wireless personal area network (PAN), a wired/wireless home area network (HAN), a wired/wireless wide area network (WAN), a campus network, a metropolitan network, an enterprise private network, a virtual private network (VPN), an internetwork, a backbone network (BBN), a global area network (GAN), the Internet, an intranet, an extranet, an overlay network, a cellular telephone network, a Personal Communications Service (PCS), using known protocols such as the Global System for Mobile Communications (GSM), CDMA (Code-Division Multiple Access), W-CDMA (Wideband Code-Division Multiple Access), Wireless Fidelity (Wi-Fi), Bluetooth, Long Term Evolution (LTE), EVolution-Data Optimized (EVDO) and/or the like, and/or a combination of two or more thereof.

Further control in accordance with the disclosure may be implemented in any type of computing devices, such as, e.g., a desktop computer, personal computer, a laptop/mobile computer, a personal data assistant (PDA), a mobile phone, a tablet computer, cloud computing device, and the like, with wired/wireless communications capabilities via the communication channels.

The many features and advantages of the disclosure are apparent from the detailed specification, and, thus, it is intended by the appended claims to cover all such features and advantages of the disclosure which fall within the true spirit and scope of the disclosure. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the disclosure to the exact construction and operation illustrated and described, and, accordingly, all suitable modifications and equivalents may be resorted to that fall within the scope of the disclosure. 

We claim:
 1. A system for compacting a mat of material comprising; collecting compaction data from at least two different areas of a mat of materials, the compaction data comprising the current level of compaction for that area of the mat; comparing the compaction data collected for each area of the mat with a desired final compaction for that area of the mat; calculating an additional compaction required for any areas of the mat requiring additional compaction; dividing the mat into subsegments requiring additional compaction based upon the collected compaction data thereby creating a compaction map; calculating an additional amount of compaction required for any subsegments requiring additional compaction; controlling a compactor based upon the calculation of additional compaction required for any subsegments requiring additional compaction by varying compaction effort of the compactor over such subsegments as the compactor travels over the subsegments to provide a final desired total compaction for each such subsegment.
 2. The system of claim 1 wherein the varying of compaction effort comprises varying of vibratory frequency or vibratory amplitude of a vibratory apparatus operatively connected to a mat-engaging implement of the compactor.
 3. The system of claim 2 wherein the mat-engaging implement is a roller.
 4. The system of claim 1 wherein the controlling of the compactor is accomplished automatically by an electronic control unit.
 5. The system of claim 1 wherein the controlling of the compactor is accomplished manually by an operator.
 6. The system of claim 1 wherein the compaction data is collected from specifically designed and implemented worksite surveys, testing, or probing.
 7. The system of claim 1 wherein the varying of compaction effort of the compactor over such subsegments is continuous.
 8. The system of claim 1 further comprising controlling the compactor to avoid subsegments that have been calculated to be compacted as desired.
 9. The system of claim 1 wherein the compactor is a smooth double drum compactor.
 10. The system of claim 1 wherein the compactor is a tow-behind compactor.
 11. The system of claim 1 wherein the varying of compaction effort comprises turning on or turning off a vibratory apparatus operatively connected to a mat-engaging implement of the compactor.
 12. A system for managing worksite machine traffic over a worksite comprising; collecting compaction data from at least two different areas of a mat of materials, the compaction data comprising the current level of compaction for that area of the mat; comparing the compaction data collected for each area of the mat with a desired final compaction for that area of the mat; dividing the mat into subsegments requiring no additional compaction based upon the collected compaction data thereby creating a compaction map; controlling a worksite machine based upon the compaction map to avoid subsegments requiring no additional compaction.
 13. The system of claim 12 wherein the controlling of the worksite machine is accomplished automatically by an electronic control unit.
 14. The system of claim 12 wherein the controlling of the worksite machine is accomplished manually by an operator.
 15. The system of claim 12 wherein the worksite machine is a hauling unit, on-road truck, off-road truck, paving machine, cold planer or reclaimer.
 16. The system of claim 12 wherein the controlling of the worksite machine includes controlling the worksite machine in real-time as the worksite machine arrives at a designated subsegment of the worksite.
 17. A system for compacting a mat of material comprising; collecting compaction data from at least two different areas of a mat of materials, the compaction data comprising the current level of compaction for that area of the mat; comparing the compaction data collected for each area of the mat with a desired final compaction for that area of the mat; calculating an additional compaction required for any areas of the mat requiring additional compaction; dividing the mat into subsegments requiring additional compaction based upon the collected compaction data thereby creating a compaction map; calculating an additional amount of compaction required for any subsegments requiring additional compaction; controlling at least two compactors based upon the calculation of additional compaction required for any subsegments requiring additional compaction by varying compaction effort of the compactors over such subsegments as the compactors travel over the subsegments to provide a final desired total compaction for each such subsegment.
 18. The system of claim 17 wherein the controlling of the compactors is accomplished automatically by an electronic control unit.
 19. The system of claim 17 wherein the controlling of the compactors is accomplished manually by an operator.
 20. The system of claim 17 wherein the controlling of the compactors includes controlling the compactors such that the compactor closest in proximity to a subsegment requiring compaction is controlled to provide the desired final compaction to that subsegment. 